The present invention relates to a closure lever particularly for sports shoes such as ski boots, roller skates or ice skates, etc.
Several types of lever are currently known. Conventional levers are constituted by a lever arm, which is pivoted at one end at adapted shoulders associated with a flap of an upper or of a shell, and has an adapted toothed surface with which the end of a cable interacts. The other end of the cable is associated with the second flap of the item of footgear.
These conventional levers do not allow to obtain micrometric adjustment of the useful length of the cable.
As a partial solution to this drawback, levers are known which have, at their lever arm, means for micrometric adjustment of the tension of the cable. For example, U.S. Pat. No. 4,553,292, discloses a quick closure means for ski boots which comprises a lever arm with which a screw is associated along a longitudinal axis. A sleeve, is coaxially associated with the screw, and its position is steplessly adjustable in a longitudinal direction; a coupling element movable with respect to the screw stem interacts with said sleeve during the tightening of a cable.
However, this solution is structurally complicated, being constituted by several component elements that must be assembled in a specific order.
As a partial solution to the described drawbacks, this same Assignee filed a U.S. patent application Ser. No. 06/297.811 on Aug. 31, 1981, related to a closure device for ski boots which comprises a lever element pivoted at one end at one of the flaps to be secured; one end of a traction element is furthermore articulated to a median portion of the lever element, and the other end is provided with a hook-like element coupleable in engagement seats formed at the other flap to be secured.
The peculiarity of the above invention is that the traction element is provided with means for adjusting its working length and with at least one substantially flexible portion; said means is constituted by a threaded pawl associated with one end of said flexible cable and rotatably engaging a threaded cavity formed at one end of said rigid bar, and by a grub screw provided at the other end and rotatably engaging a threaded seat formed in the hook-like element.
Even this solution, however, has drawbacks which essentially concern structural complexity, due to the considerable number of elements used, and the need to use connecting rivets or pivots, thus increasing the manufacturing costs of the device.
Furthermore, in order to adjust the useful length of the cable it is necessary to disengage the hook from the openings formed on the block, and once adjustment has been achieved it is necessary to re-associate the hook with the openings.